Preheat the oven to 160°C.
Heat olive oil in a large casserole dish.
Cook onions, garlic, and thyme for 4 minutes.
Set the cooked onion mixture aside.
Sear lamb chops in the casserole dish until golden brown.
Place the onion mixture back on top of the chops.
Pour lamb stock over the meat and onions until covered.
Blanch potato slices in hot oil or clarified butter for 30 seconds.
Drain potatoes and arrange them over the onions.
Dot 50g of butter over the potatoes.
Bake in the oven for 90 minutes until tender.
Boil vinegar and sugar in a saucepan while stirring.
Simmer for 10 minutes until reduced by a third.
Pour the vinegar reduction over the sliced red cabbage.
Chill in the fridge for 24 hours before serving.
Serve the lamb hotpot with the pickled cabbage.